Sorry if I wasn't clear enough. I wasn't talking about a P2P setup but a setup where the server is only required to deal with "active" packets that are constantly being bounced back and forth between the players. That's what the whole analogy about the server being the postal system ties into.

The plug-in is in AU Resources. Got it confused with AUM. It's the "Sub levels 3" plug-in by Dirk Mittler about 1/5 of the way down the page. The readme says you have to designate createboxes across the map to determine how much the computer will load at a time.

My main concern was that 3DGS isn't robust enough to run an MMO that (I hope) will prove to be successful. It sounds like that isn't so much of an issue.